The report states that temperature records were set in every state and territory over summer.

It says much of Australia has been drier than usual since the middle of last year.

While Queensland and New South Wales have experienced heavy rainfall, Victoria and South Australia have recorded their driest summer in decades, and there have been devastating bushfires in at least three states.

Professor Will Steffen, who authored the report, says the findings are indicative of a trend that shows an increase in extreme weather events.

"Over the last 50 years, we've seen a doubling of the record hot days, we're getting twice as much record hot weather than we did in the mid-20th century, [and] we're getting less cold weather," he said.

"In fact, if you look at the last decade, we're getting three times as many record hot days as we are record cold days, so the statistics are telling us too that there's an influence on extreme events - they're shifting."